Electrical insulation tape, film backing thereof, and method of manufacturing the film backing

Abstract

An electrical insulation tape, film backing thereof, and method of manufacturing the film backing. The film backing comprises about 20 to 80 parts by weight of polyethylene, about 80 to 20 parts by weight of EPDM rubber, about 0 to 30 parts by weight of fillers, 0 to 50 parts by weight of flame retardant, and about 0 to 20 parts by weight of processing aids. The film backing has physical properties similar to PVC film backings, and thus can replace the PVC film backing used in the electrical insulation tape.

1 . An electrical insulation tape film backing, comprising: 
 to 80 parts by weight of polyethylene,    80 to 20 parts by weight of EPDM rubber,    0 to 30 parts by weight of fillers,    0 to 50 parts by weight of flame retardant, and    0 to 20 parts by weight of processing aids.    
     
     
         2 . The film backing as claimed in  claim 1 , wherein the film backing has a tensile strength of 1.3 to 3.0 kgf/mm 2 .  
     
     
         3 . The film backing as claimed in  claim 1 , wherein the film backing has an elongation at break of 100% to 700%.  
     
     
         4 . The film backing as claimed in  claim 1 , wherein the film backing has a breakdown voltage of 39 to 150 kv/mm.  
     
     
         5 . The film backing as claimed in  claim 1 , wherein the film backing has a recovery from deformation of 5 to 20%.  
     
     
         6 . The film backing as claimed in  claim 1 , wherein the film backing has a thickness of 0.02 to 0.30 mm.  
     
     
         7 . An electrical insulation tape, comprising: 
 a film backing comprising 20 to 80 parts by weight of polyethylene, 80 to 20 parts by weight of EPDM rubber, 0 to 30 parts by weight of fillers, 0 to 50 parts by weight of flame retardant, and 0 to 20 parts by weight of processing aids; and    an adhesive coated on one surface of the film backing.    
     
     
         8 . The electrical insulation tape as claimed in  claim 7 , wherein the film backing has a tensile strength of 1.3 to 3.0 kgf/mm 2 .  
     
     
         9 . The electrical insulation tape as claimed in  claim 7 , wherein the film backing has an elongation at break of 100% to 700%.  
     
     
         10 . The electrical insulation tape as claimed in  claim 7 , wherein the film backing has a breakdown voltage of 39 to 150 kv/mm.  
     
     
         11 . The electrical insulation tape as claimed in  claim 7 , wherein the film backing has a recovery from deformation of 5 to 20%.  
     
     
         12 . The electrical insulation tape as claimed in  claim 7 , wherein the film backing has a thickness of 0.02 to 0.30 mm.  
     
     
         13 . A method of manufacturing an electrical insulation tape film backing, comprising the steps of: 
 (i) providing a mixture of polyethylene and EPDM rubber;    (ii) forming a film from the mixture by melting the mixture at 100 to 240° C.;    (iii) drawing the film at a stretch ratio of from 1:1 to 1:10 in two perpendicular directions; and    (iv) performing a surface treatment on the film obtained from the step (iii).    
     
     
         14 . The method as claimed in  claim 13 , wherein, the mixture of the step (i) contains 20 to 80 parts by weight of polyethylene and 80 to 20 parts by weight of EPDM rubber.  
     
     
         15 . The method as claimed in  claim 14 , wherein the mixture further contains fillers.  
     
     
         16 . The method as claimed in  claim 14 , wherein the mixture further contains flame retardants.  
     
     
         17 . The method as claimed in  claim 14 , wherein the mixture further contains processing aids.  
     
     
         18 . The method as claimed in  claim 14 , wherein the mixture further contains colorants.  
     
     
         19 . The method as claimed in  claim 13 , wherein, in the step (ii), a film is formed from the mixture by melting the mixture at 140 to 180° C.  
     
     
         20 . The method as claimed in  claim 13 , wherein, in the step (ii), a film is formed by blow molding, single screw extrusion molding, twin screw extrusion molding, or calendaring.  
     
     
         21 . The method as claimed in  claim 20 , wherein, in the step (ii), forming a film is performed by single screw extrusion molding with a screw of 90 mm in diameter and the ratio of the length to the diameter of the screw is 30.  
     
     
         22 . The method as claimed in  claim 13 , wherein the surface treatment is corona treatment or chemical treatment.  
     
     
         23 . The method as claimed in  claim 13 , wherein, after the step (i) and before the step (ii), further comprising the step of: 
 pelletizing the mixture.